What I don't understand with these technologies, is how you do continuous deployment without breaking all running client sessions evertime.
1. It includes live navigation, which updates the URL as you interact with the app. For example, if you try the live scaffold generator in Phoenix v1.5.0-rc.0, you will see that once you click the "New Post" modal, the URL changes to "/posts/new". So if users reconnect by any reason (poor connection, new deployment, etc), they will go back to the same page with the same modal.
2. For forms, we automatically submit the current form state on reconnections, allowing the server and client to sync up.
For complex applications, think a chat app or a game, then you have to persist messages, the game state, and what not on the server. But that would be necessary regardless if you are using LiveView or not.
It's good to note that using the live navigation you can pass parameters via the URL. That's my main method for graphing / data view pages.
And iirc I believe LiveView will have all the state necessary client-side to be able to reconstruct the session when reconnecting the socket. I’m not near my development machine to make sure on that one though.
Liveview is built on top of channels, so worth reading up about them: https://hexdocs.pm/phoenix/channels.html